Suction cleaner



' M. D. STAHL SUCTION CLEANER Feb; 22, 1944.

Original Filed April 8, 1939 2 Sheets-Sheet 1 Maurice Stal ATTORNEY Feb.22, 1944. D. STAHL 22,445

SUCTION CLEANER Original Filed April 8, 1959 2 Sheets-Sheet 2 INVENTORMaurice fl. Slalzl ATTORNEY Reissued Feb. 22, 1944 Re. 22, i45

22,445 suc'rlou CLEANER Maurice D. Stahl, North Canton, Ohio, assignorto The Hoover Company, North Canton, Ohio, a

corporation of Ohio Original No. 2,260,237, dated October 21, 1941, Se-

rial No. 266,721, April 8, 1939. Application for reissue April 20, 1942,Serial No. 439,779

11 Claims. (01; 183-36) This invention relates to improvements insuction cleaners and more particularly to an improved form of mufilerfor suction cleaners'serving to reduce thenois'e due to the rush of airthrough the suction system.

One practical method of reducing so-calledairflow noises is to provide amuliier extending beyond the outlet from the fan chamber and con sistingof a tubular member lined with a suitable absorbing material. However,there are certain practical limitations in the use of mufflers,particularly when adapted to a cleaner having a pivotally mounted handlesupporting the outer end of a'dirt bag; In such an arrangement, themuffler extended within the dirt bag becomes a definite obstruction tothe free movement thereof as it swings with the handle unless themufiler be made s'ufliciently flexible to bend with the bag and then itis very likely to kink, thus closing ofi the discharge passage entirely.I

Therefore, the object of the present invention is to provide an improvedmufiler arrangement whereby the efiective area of sound-absorbingsurface is'obtained without unduly extending its length into the dirtbag. Briefly, this result is obtained by including a portion of themuffler within the exhaust passage leading from the fan chamber andconnecting it with the external portion through an intermediate flexiblesection, so that the muffler becomes an articulated unit. And aside fromthe advantage of decreased length of mufller throughout its externalportion, there is the further novel feature of treating the normalcleaner exhaust passage for noise-reduction for it is in this regionthat a considerable part of the noise is created, due to the; turbulenceset up by the sudden change of velocity of the air leaving the fanchamber.

A preferred embodiment of the invention will now be described inconnection with the accompanying drawings, in which:

Figure 1 is a general view in side elevation of atypical suction cleanerwith portions'broken away to show the suction system and the articulatedmufll'er arrangement;

Figure '2 isa viewsimilarto Figure '1 showing the dirt bag and mufflerassembly removed from thecleaner;

Figure 3 is a top plan view of the rear end portion of the cleaner withportions broken away to show themuffier arrangement;

Figure 4 is a'view inside elevation of the rearmost sectionof thecleaner showing a modified arrangement in 'which'the dirt bag is mountedupon the outer section of themufiler rearwardly of the flexible sectionrather than forwardly thereof as shown in Figure 1.

The suction cleaner herein disclosed and to which the improvedarticulated mufller is particularly adapted, is of the standard designwherein the cleaner body is supported upon wheels to be .maneuvered overthe carpet surface by means of a handle" having pivotal connection withthe cleaner body.

The cleaner comprises generally, a casing I supported upon pairs offront and rear wheels 2, 2 and includes a nozzle portion 3 extendingacross its forward end. A fan chamber 4, located centrally of the'casing I; houses a fan 5 driven by" a motor concealed beneath theremovable dome-like cover 6 supported upon the casing I. The handle 1 isprovided at its lower end with an inverted U-shaped bail la whichstraddles the motor cover 6 and has pivotal connection with thecleaner'casing. The handle is free to swing forwardly and rearwardly asthe cleaner is maneuvered over the carpet surface with the customaryreciprocating motion. Referring now in greater detail to thesuctioncreating system, the nozzle portion 3 has the form of a chamberwith a downwardly opening suction mouth and is normally spaced incleaner operation in close proximity to the carpet surface, An airpassage extends rearwardly from the nozzle chamber and communicates withthe fan chamber through an annular inlet opening or eye 4a in itsbottomwall. By preference, a rotary carpet-contacting member 8 ismounted in the nozzle chamber and is driven by means of a belt'Bextending rearwardly through the 'air passage from the nozzle and havingdriving connection with the fan 5 through a pulley 10 formed at thelower end -of an extension 50. 'of the fan hub.

Extending rearwardly'from' the fan chamber and-slightly oblique to thelongitudinal center line of the cleaner body is the exhaust passage I Ithrough which the dirt-laden air is discharged into a dirt bag 12 of theusual porous fabric construction having its lower end detachablyconnected to the discharge outlet of the fan chamber and its outer endsuspended from the handle 1. The extreme rear end of the exhaust passageII is preferably flanged at llato provide a seat to which the dirt bagsupporting ring I3 is removably clamped.

In the present disclosure, this bag ring i3 is incorporated in themuffler assembly, but considered merely as an attaching 'fitting for themouth portion of the bag I2, it hasthe general iormof a ring which fitsflush against the in Figure 3. The mouth'of the bag I2 is secured aroundthe ring l3 in any suitable manner as for instance, by means of a metalclamping ring 15 inserted in the mouth of the bag and seating on ashoulder on the outer face of the ring.

Referring again to the discharge outlet passage I I, the same leadsrearwardly from the fan,

chamber in a direction slightly oblique to the longitudinal axis of thecleaner body, so that the dust-laden air leaves the fan chamber in apath generally tangential to the periphery of the fan. Immediatelybeyond the portin the fan chamber defined by the entrance to the exhaustpassage, the latter undergoes an abrupt increase in its horizontal andvertical cross-sectional dimensions as indicatedbythe rearwardly 'facingshoulders llb formed just beyond the port; Moreover, the exhaust passageH is rec- ,tangular in cross section, somewhat elongated horizontallyand having a slightdivergence to- ;ward its outer end as shown in Figure3. :fiKNow, the increase in the dimensions of the exhaust passage Hbeyond that otherwise necessary for handling the air discharged from thefan chamber is a matter of approximately an inch in 'eachdirection, thisenlargement making possible the accommodation of a portion of themuiller which preferably formsa part of a detachable bag and'mufilerassembly now to be described in detail.

"Generally, the mufiler has the form of a tubular memberconsisting of anouter shell and an inner lining composed of a-relatively thick layer I 9of any'suitable sound-absorbing materialsuch as spongerubber, cellulosepadding or like material. 7

In the mufller arrangement disclosed, a sectional construction has beenadopted so as to introduce a certain degree of flexibility-intermediateits end portions and for the reasons already mentioned. Thus, as clearlyshown in Figure 1, the mufller proper is madeup. of an internal sectionl6 extending forwardly from the bag supporting ring 13 and into theenlarged exhaust passage I l. Rearwardly beyond the internal section isa flexible bellows-like section I! extending a short distance beyond thesupporting-ring I3 and flnally,-there is an external section I8 whichprojects into the lower end portionof thedirt bag I2 and is inclinedslightly in an upward direction following generally the inclination ofthe bag itself. -01 Referring now to some of the details of constructionof themufller, the internal section 16 which fits into the enlargedexhaust passage H, includes the outer metallic shell" Ilia enclosing itsportion of thesound-absorbing member l9 and suitably fastened to thesupporting ring 13. In'additionto the enclosing metallic shell .I'Ea,the internal section lfi'is preferably provided'with "a" perforated.sheet metal inner liner 20 as apro'tectorfor the soft sound-absorbingmaterial against the severe abrasive effect of the dirt particles andother objects discharged from the fan chamber. vIn fact, along one sideof the exhaust passage, as shown in Figure 3, it may be desirable toomit the sound-absorbing lining entirely, because of the likelihood ofpins and other pointed objects being driven against the sub face withsuch force as to penetrate the perforations and become firmly embeddedin the soundabsorbing material. However, the treatment of thesound-absorbing surface throughout the exhaust passage is a matter ofchoice, although it can be stated that the use of a perforated sheetmetal liner does not reduce-the effectiveness of the sound-absorbinglayer materially.

In any case, the internal section I6 extends through the supporting ringl3 where it joins the short angular flexible section l1 which preferablyconsists of a bellows constructed of a suitable fiexible sheet material,so that it can flex readily through a limited angle in the movement ofthe outer section l8.

The outermost section I8 is essentially a continuation of theintermediate flexible section I! and includes the greater length of thesoundabsorbing material, but preferably omits the perforated metallining, it being assumed that the material is capableof withstanding theabrasive effect of the dirt. particles throughout this portion of themufllen ,In any. case,fthe outer section is of rigid,v constructionlbyreason of its enclosing metal shell, [8a which houses and supports thesound-absorbing material l9. And finally, it is preferred to'increaseslightly the diameter of the air passage throughout the flexible andouter muiller sections I1 and [8; so as to reduce any tendency forthecreation of a back-pressure by. reason of any restrictive effeet on themufller.

Owing to the weight. of the extended .outer muiiler section [8, it isfurther desirable to support it upon the ring l3 by means of a suitablehinged connection as at 2|, just above the flexible section II. Thehinge may be of any simple construction, as a pin, joining the ends -ofshort arms projecting toward each other from the upper edges of the ringl3. and the corresponding point of a ring-like. fram member lBb at thebase of the outer shell I811. forming the body of the outer muiilersection [8. A torsion spring 22 is incorporated in the hinge and acts 1to support the weight of the flexibly supported muffler section 18.

A possible modification or alternative muffier and dirt bag arrangementis disclosedin Fig-v ure 4 wherein a principal change is the mounting ofthe: lower end of the bag 23 around the base of the outermost section24' of the mufller, rather than upon the bag-supporting-ring I3, as isthe case in Figure 1. In other words, the dirt bag 23 is now supportedupon the hinged portion of the mufllerand therefore swings with itrather than being fixed tothe cleaner casing. This provides for asomewhat more flexible construction, but at the sametime-exposes theintermediate flexible portion of the mufller, as well as the hingedconnection between the outer muffler section 24 and the supportingring'25. Ring 25 is similar to the supporting ring l3-shown in Figure 1,exceptthat the seat-for the bag mouth is omitted, this havingbeen-transferred to the annular base 24a of the-hinged muilier sectionwhich is now formed with- "an'annular channel about which the bag mouthis? clamped through the medium of the same type of clamp ing ring 23a asused in'the previous arrangement. A second principal change comprisesthe provision of a continuous sound-absorbing lining 19 which extendsthe entire length of the muffler assembly including the bellows-likecentral part instead of merelywithin the inner and outer sections as intheflrst'embodiment;

With thebag supported upon' the hinged portion of the 'mufiler, it' maybe necessar'y'toprovide a more substantial hinged connection at B -andto use a'stro'nger torsion spring at the hinge. This is a; detail-whichcan be readily taken care of in thedesign of the mufiler mounting. As'the sound-absorbing liner 19 extends the entire length of the muffler itmust be capable of flexure between v the inner and outer sections at thebellows 21. With the flexible portionof themufller exposed toview andalso to' a greater degree of wear, it is preferable to enclose theflexible sectiono'f the sound-absorbing material within a short bellowsmember 2'! formed of some suitable sheet material, into which thesound-absorbing material is pressed or molded, but otherwise maintainingits continuity throughout the full length of the muffler. In otherrespects the bag and muiller are assembled and removably attached to theoutlet connection from the cleaner, in the same manner as hereinbeforedescribed.

From the foregoing description, the advantages of the mufilerarrangements hereinbefore mentioned will be readily appreciated. firstplace, the over-all length of the muffler has not been sacrificedalthough the efiect of decreased length has been attained by inserting aportion of its length into the body of the cleaner and throughout theexhaust passage which ordinarily is not treated for noise reduction.Another advantage is the practical application of a mufller to a cleanerof the type in which the handle swings relatively to the cleaner bodyand supports the outer end of the bag, thus introduc- 1 lug considerableflexing at the mouth portion of the bag and otherwise making it quiteimpractical to use a muffler of any considerable length.

And finally, with the mufiier forming an integral part of the bagassembly, it is possible to make renewals and replacements quite easily,inasmuch as the muffler is removable from the cleaner as a unit andhence readily accessible. In fact, this arrangement lends itself to theuse of a muffler unit capable of being assembled as a part of the bagmounting. either for ready replacement in case of wear, or, in the eventthat it is deemed desirable to provide muiliers as v optional equipment,to be attached or not as the user desires.

Thus, without limiting the invention to the specific features ofconstruction herein disclosed, I claim:

1. In a suction cleaner, the combination with suction-creating meansincluding a fan chamher having a passage leading to the exhaust outlettherefrom, of a muffler comprising a tubular member of sound-absorbingmaterial and adapted to be attached at said exhaust outlet with aportion of its length extending into said hassage to form asound-reducing lining therefor.

2. In a suction cleaner, the combination with suctiomcreating meansincluding a fan chamber having an exhaust passage of substantiallyincreased transverse dimensions leading to a flanged outlet, of amuffler comprising a relatively thick tubular body of sound-absorbingmaterial adapted to be attached to said flanged outlet with a portion ofits length extending through out the length of said exhaust passage andforming a conduit for the air discharged from said fan chamber.

3. In a suction cleaner, the'combination with suction-creating meansincluding a fan chamber In the having an exhaustpassage ofsub'stantiallyincreased transversedimension leading to a flanged outlet,of a mufiler comprising a tubular body of I sound-absorbing materialadapted to be attached haust passage and another portion extending fromand beyond said exhaust passage.

5. Ina suction cleaner, the combination of suction-creating meansincluding a fan chamber having an exhaust passage, a dirt bag adapted tobe attached to the outlet from said exhaust passage, and a mufllercomprising a tubular member of sound-absorbing material divided intosections, one section being adapted to fit within and form a lining forsaid exhaust passage and the other section projecting beyond the outletfrom said exhaust passage and into said dirt bag.

6. In a suction cleaner, the combination of suction-creating meansincluding a fan chamber having an exhaust passage, a dirt bag adapted tobe attached to the outlet from said exhaust passage, and a mufilercomprising a tubular member with walls of sound-absorbing materialhaving a portion extending throughout the length of said exhaust passageand a portion projecting beyond said outlet and into said dirt bag, andmeans for attaching said muffler at said outlet.

'7. In a suction cleaner, the combination of suction-creating meansincluding a fan chamber having an exhaust passage and a flanged outletconnection, and a muffler comprisin a tubular member having a lining ofsound-absorbing material and divided into flexibly connected sections,

one section being adapted to fit within said exhaust passage with theother section projecting from and beyond said outlet, and a fittingcarried by said muliler for detachably connecting the same to saidoutlet connection.

8. In a suction cleaner, the combination of suction-creating meansincluding a fan chamber having an exhaust passage substantially enlargeddiametrically and a flanged outlet connection, a d rt bag adapted fordetachable connection at said outlet connection, and a mufllercomprising a pair of flexibly connected sections consisting ofsubstantially rigid tubular members lined with suitable sound-absorbinmaterial, one of said sections being adapted to fit within the enlargedexhaust passage to form a sound-absorbing lining therefor and the othersection projecting beyond said outlet connection and into said dirt bag,and an attaching fitting intermediate the flexibly connected sections ofsaid muflller for connecting the same to said flanged outlet connection.

9. In a suction cleaner of the type havin an ambulatory body includingair-moving means, and dust bag; an articulated sound-absorbing mufflercomprising longitudinally spaced sections each consisting of a rigidmetallic casing lined with sound-absorbing material and means pivotallyinterconnecting said sections and including rigid hinge means and aflexible bellowslike conduit, one of said section being fixedly carrieddirectly by said body and forming a part of the exhaust outlet of saidair-moving means and the other extending movably therefrom, said 'bagenclosing-said last mentioned section and said bellows-like conduit.

10. In a suction cleaner of the type having an ambulatory body includingair-moving means, and a dust bag; an articulated sound-absorbing mufiiercomprisin longitudinally spaced sections each consisting of a rigidmetallic casing lined with sound-absorbing material and means pivotallyinterconnecting said sections and including rigid hinge means and aflexible bellows-like conduit, one of said sections being fixedlycarried directly by said body and forming a part of the exhaust outletof said air-moving means and the other extending movably therefrom, saidbag enclosing and being movable with said last men tioned section.

11. In a suction cleaner of the type having an ambulatory body includingair-moving means, and a dust bag; an articulated sound-absorbing muiilercomprising longitudinally spaced sections each consisting of a rigidmetallic casing, means pivotally connecting said sections and includingrigid hing means and a flexible bellows-like conduit, a sound-absorbinglining extending the full length of said muiiier including saidbellows-like conduit, characterized in that one of said sections iscarried directly by said body and forms a part of the exhaust outlet ofsaid air-moving means and in that the other section is enclosed by saidbag which is movable therewith.

MAURICE D. STAHL.

